107091032

1.What is the 5th element in the original list of ages?

exam = read.table(file='customers.txt',header = TRUE)
ages=exam$age
ages[5]
## [1] 45

2.What is the fifth lowest age?

sort_age1=sort(ages)
sort_age1[5]
## [1] 19

3.Extract the five lowest ages together

sort_age1[c(1:5)]
## [1] 18 19 19 19 19

4.Get the five highest ages by first sorting them in decreasing order first.

sort_age2=sort(ages,decreasing= TRUE)
sort_age2[c(1:5)]
## [1] 85 83 82 82 81

5.What is the average (mean) age?

mean(ages)
## [1] 46.80702

6.What is the standard deviation of ages?

sd(ages)
## [1] 16.3698

7.Make a new variable called age_diff, with the difference between each age and the mean age

age_diff = abs(ages-mean(ages))
head(age_diff,5)
## [1]  2.192982 22.192982  5.807018 26.192982  1.807018

8.What is the average “difference between each age and the mean age”?

mean(age_diff)
## [1] 12.66948

9.Visualize the raw data as we did in class: (a) histogram

hist(ages)

  1. density plot
plot(density(ages))

  1. boxplot+stripchart
boxplot(ages, horizontal = TRUE)
stripchart(ages, method = "stack", add = TRUE)